Abstract
A 2:1 regular interstratified illite-smectite (ISI) has been found in the hydrothermal alteration zone of the Toyoha mine accompanying a 1:1 regular interstratified (IS) and nonregular interstratified I/S. These coexisting regular ISI and IS constituents are examined by XRD through refinement and simulation processing of their complicated XRD patterns. The basal reflections of the ISI constituent are very close to an integral series, yielding mean d(001)=35.36±0.13Å with CV value of 0.53% for the 12 reflections in air-dry and mean d(001)=36.98±0.11Å with CV value of 0.42% for the 12 reflections after glycolation. The CV values less than 0.75% are decisive of high degree of regulation, revealing a proper 2:1 regular interstratified illite-smectite with complete ordered ISI succession. The IS constituent is also equally a proper 1:1 regular interstratified illite-smectite with complete ordered IS succession, that is rectorite giving mean d(001)=25.13±0.10Å in air-dry and mean d(001)=26.98±0.12Å after glycolation. The existence of ISI regular intestratified is to be significant in terms of fundamental particles constructing illite-smectite interstratified system.
